Compact Differential Rectangular Dielectric Resonator Antenna

In this letter, a compact differential hollow dielectric resonator antenna (DRA) is investigated. The hollow DRA is fed by two identical conducting strips connected to the outputs of an underlaid 180° hybrid coupler (rat-race). With this compact configuration, loss of the feed network can be minimized and, thus, the differential gain can be made about the same as for the single-ended case. By using the differential feed, the DRA can be integrated with differential integrated circuits directly. Also, its cross-polarized fields are generally weaker than those of the single-ended version. The reflection coefficient, radiation pattern, and antenna gain of the proposed differential DRA are simulated, and the result agrees reasonably with our measurement.